Understanding variability associated with corn grain yield response to foliar fungicide application

Marshall, John

Permalink

https://hdl.handle.net/2142/49587 Copy

Description

Title

Understanding variability associated with corn grain yield response to foliar fungicide application

Author(s)

Marshall, John

Issue Date

2014-05-30T16:51:15Z

Director of Research (if dissertation) or Advisor (if thesis)

Below, Frederick E.

Department of Study

Crop Sciences

Discipline

Crop Sciences

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Strobilurin
• Corn

Abstract

Quinone outside inhibitor (QoI) fungicide (e.g., pyraclostrobin, azoxystrobin, and trifloxystrobin) fungicide application is becoming a common practice in corn production systems. The strobilurin class of fungicides inhibits mitochondrial respiration in fungal cells, and preventing plant pathogen infection. In addition, these compounds have been shown to decrease ethylene biosynthesis and reduce oxidative stress in plants. Yield response to fungicide application tends to be highly variable as a result of varying disease pressure, but may also be affected by environmental factors and management practices that influence corn yield potential. The focus of this research was to determine if there is a differential yield response to strobilurin fungicide application under standard and intensive management systems. The standard management system in this study consisted of crop input levels that are consistent with current university recommendations (i.e., adequate soil fertility, 180 lb N, and a plant density of 32,000 plants per acre). In contrast, the intensive management system consisted of extra P fertility, extra side-dress N, a plant density of 45,000 plants per acre, and application of a strobilurin fungicide during the tassel stage. Treatments were designed to assess the yield difference associated with adding a fungicide treatment to the standard and intensive management system. A combined analysis of 30 site-years (2009 to 2013) indicated that adding a fungicide application to the basic system did not result in a significant yield increase (+3.5 bushels per acre; P = 0.17), while the addition of fungicide in the intensive system led to a 8.8 bushel per acre increase in yield (P < 0.01). Individual data sets contributing to the overall analysis were divided into three groups based on their mean yields (150 to 175, 175 to 200, and greater than 200 bushels per acre) to investigate the influence of yield potential on fungicide response. In general, response to fungicide increased as the yield potential of an environment increased, especially for the iii intensive management system. The results of this research could provide corn producers a valuable guide to determine if strobilurin fungicide application is warranted based on the estimated yield potential of their crop and other contributing factors like management system.

Graduation Semester

2014-05

Permalink

http://hdl.handle.net/2142/49587

Copyright and License Information

Copyright 2014 John Marshall

Owning Collections